Cepheus

Cepheus (abbreviation: Cep), the King, father of Andromeda, is a northern constellation, mostly circumpolar
from as far south as latitude 30° N, with a noticeable quadrilateral
shape made from Alpha, Beta, Iota, and Zeta.

Cepheus contains several variable
stars that are prototypes of their classes, the most important of which
is Delta Cephei. VV Cep is a huge eclipsing
binary of the Zeta Aurigae type, consisting
of a red supergiant and a smaller blue companion in a 20.3-year orbit (magnitude
range 4.7 to 5.4; R.A. 21h 56.7m, Dec. +63° 38').

There are also two
interesting open clusters. NGC 6939
is a fine cluster of about 80 stars in a rich field that includes NGC 6946,
a face-on spiral galaxy. It lies 2.5° south of Theta Cep and 2°
southwest of Eta Cep (magnitude 7.8, diameter 7.8'; R.A. 20h 31.4m, Dec.
+60° 38'). NGC 188 contains about 120 stars and is possibly the oldest
known open cluster, with an age of about 5 billion years (magnitude 8.1;
diameter 14'; distance 5,000 light-years; R.A. 00h 44.5m; Dec. +85°
20'). See below for details of the constellation's brightest stars.

Gyulbudaghian's Nebula

Gyulbudaghian's Nebula (HH215) is a Herbig-Haro object –
a variable bipolar nebula generated by shock
waves from a contracting protostar – in Cepheus.
At the apex of its faint, fan-like shape lies the variable star PV Cephei,
which provides the energy that illuminates the nebula. HH 215 resembles
the classic variable bipolar nebula NGC 2261 ( Hubble's
Variable Nebula) as it varies in shape and brightness and its spectrum
is in a state of continual change.

The name "Gyulbudaghian's Nebula" (pronounced gyool-boo-DAH-ghee-an) originates
from a paper published in Soviet Astronomy Letters (1977).